Obvious that he had anger issues as well.
Just read the part where he went to the party a few days before his 22nd birthday to give the world "a one last chance" and ended up getting his ass kicked.
I mean, the guy was enraged and jealous of the girls and the guys there that he started to insult them at their own party. Then right after, he tried to push the girls off the 10 foot ledge. Which didn't go so well, since the guys pushed him off instead, breaking his left ankle.
Later when he got his ass kicked for coming back to the party to find his stolen stuff, he expected other girls to help him out of the situation that he rashly got himself into initially by trying to push people off the ledge.
He could've just chilled, relaxed, sipped on some beer, played a little beer pong, started some conversations with other people, but instead he threw insults at them. What the fuck did you expect? For someone his age, he's not very smart.